描述

The LM73605/LM73606 family of devices are easy-to-use synchronous step-down DC-DC converters capable of driving up to 5 A (LM73605) or 6 A (LM73606) of load current from a supply voltage ranging from 3.5 V to 36 V. The LM73605/LM73606 provide exceptional efficiency and output accuracy in a very small solution size. Peak current-mode control is employed. Additional features such as adjustable switching frequency, synchronization to an external clock, FPWM option, power-good flag, precision enable, adjustable soft start, and tracking provide both flexible and easy-to-use solutions for a wide range of applications. Automatic frequency foldback at light load and optional external bias improve efficiency over the entire load range. The family requires few external components and has a pinout designed for simple PCB layout with optimal EMI and thermal performance. Protection features include thermal shutdown, input undervoltage lockout, cycle-by-cycle current limiting, and hiccup short-circuit protection. The LM73605 and LM73606 devices are pin-to-pin compatible for easy current scaling.

特性

Synchronous Rectification

Wettable Flanks QFN Package (WQFN)

Low Quiescent Current

0.8 µA in Shutdown (typical)

15 µA in Active Mode with No Load (typical)

Wide Voltage Conversion Range:

tON_MIN = 60 ns (typical)

tOFF_MIN = 70 ns (typical)

Low MOSFET ON-Resistance:

RDS_ON_HS = 53 mΩ (typical)

RDS_ON_LS = 31 mΩ (typical)

External Bias Input to Improve Efficiency

Pin-Selectable Auto Mode or Forced PWM Operation

Adjustable Frequency Range: 350 kHz to 2.2 MHz

Synchronizable to External Clock

Internal Compensation

Power-Good Flag

Precision Enable to Program System UVLO

Flexible Soft-Start Features:

Start-up into Pre-Biased Load

Fixed or Adjustable Soft-Start Time

Output Voltage Tracking

Cycle-by-Cycle Current Limiting

Short-Circuit Protection With Hiccup Mode

Thermal Shutdown Protection

Create a Custom Design With the WEBENCH® Power Designer using LM73605 or LM73606